I have a MySpace account. Don't use it. :D I wouldn't even have one if a friend of mine didn't force me to.
I'd have Facebook if I could get my university e-mail to work ._. But that's only because all the girls in the dorm use it except for me and another girl. It'd be nice to see what was going on with them, you know? Or something like that. *shrug*
Never heard of Bebo either.
Personally, I use Livejournal, even if it's not like anything above. I like having an online journal.